In article et,
rijo wrote:

Hi group , I need to know what type of varnish is used on electrical
windings . I have several projects that will require varnish coated
copper wire . Thanks for any good answers to my question in advance . Rick

If you're winding your own coils, start with wire that's already coated.
I've wound guitar pickups, power and output transformers for tube
amplifiers, and coils for magnetic bearings. I usually buy wire from
MWS, although I imagine there are other suppliers, too.

You have a choice of several different insulating coatings. Some will
melt with the heat of a soldering iron, which makes termination easy,
and others require mechanical stripping.

Beyond the insulating varnish, you can also buy wire with an additional
coating that melts in an oven, fusing the coils together and making the
coil rigid without a core or bobbin. There are also coatings that melt
with solvent, and pulling the wire through a damp sponge of solvent
bonds the coils together.

To keep the coils quiet, if they aren't bonded by heat or solvent, you
can vacuum pot them in melted paraffin, or some commercial potting
compound.